1. Field of the Invention
The present invention relates to a clock spring connector which electrically connects between a fixed body and a movable body by means of a flat cable etc., particularly relates to a lock mechanism for accurately adjusting the relative locations of the fixed body and the movable body and retaining the relative locations until the clock spring connector is installed on a steering apparatus.
2. Description of the Related Art
A clock spring connector which electrically connects between a fixed body and a movable body is installed in a steering apparatus of an automotive vehicle, and is utilized as a connecting means to an air bag or other devices. In this case, it is required that the movable body be installed on a steering wheel so as to be able to turn substantially the same angle from a neutral position of the steering wheel in either direction. For this reason, a mechanism is often provided which serves as an indicator for locational adjustment between the fixed body and the movable body.
One such mechanism is constituted such that either of the fixed body and the movable body is equipped with a rotational member having a gear, and the other of the fixed body and the movable body is equipped with an engaging member capable of engaging the gear of the rotational member. And, on every one complete revolution of the movable body, the gear engages the engaging member and rotates by a predetermined angle in response to the movable body. Therefore, when a particular tooth in the gear is positioned and the movable body is positioned at a predetermined position with respect to the fixed body, the gear is to be positioned at a neutral position.
Thus, markings are put on the particular tooth in the gear and a member pointing to this gear. When installing the clock spring connector on the steering apparatus, by makeing these markings face each other, the movable body can be installed at the neutral position with respect to the fixed body.
Further, it was necessary to retain the movable body at the neutral position with respect to the fixed body before installing an assembly consisting of the movable body and the fixed body into the steering apparatus. The Japanese Unexamined Patent Application No. SHO 62-18355 discloses a locking mechanism for this end. The locking mechanism described in this prior art reference has a lock member provided with a clip pin and an engaging projection. The clip pin is engaged into a hole opened on the movable body by utilizing a snapping action, and the engaging projection is engaged into a concave portion formed on the fixed body. The lock member is removed after finishing the installation of the steering apparatus.
However, since above-described locking member is constituted in such a manner that the clip pin is integrally formed from a hard material like plastic, and can be engaged with or disengaged from the clock spring connector by snapping in the clip pin into the hole opened on the movable body or snapping out from it, there was a problem such that, if the snapping strength of the clip pin is enhanced in order to protect the lock member from unexpectedly falling off during its shipment or transportation, removing the lock member becomes fairly troublesome when installed in the steering apparatus. Further, it was feared that the clip pin could break if the lock member was forcibly removed, and broken pieces of the clip pin would remain in the steering apparatus and generated strange sounds when the automotive vehicle was running.